1.1.3.3 Back–End Tier 2

The back-end tier is where client requests are processed and business services are performed. The back-end hardware hosts software components that make up tier 2. Here, the Sun Java System Messaging Server component handles all user operations for accessing mailboxes and handling inbound and outbound mail. The Sun Java System Calendar Server handles all interaction between users and their calendars, including email notifications through Messaging Server.

The business services on the back-end hardware also includes the security and identity verification provided by Sun Java System Access Manager and Sun Java System Directory Server.